An extract on #rihannanavy
Battles affect the individuals who take part, as well as the political actors. Personal effects of battle range from mild psychological issues to permanent and crippling injuries. Some battle-survivors have nightmares about the conditions they encountered, or abnormal reactions to certain sights or sounds. Some suffer flashbacks. Physical effects of battle can include scars, amputations, lesions, loss of bodily functions, blindness, paralysis and death.
Battles also affect politics. A decisive battle can cause the losing side to surrender, while a Pyrrhic Victory such as the Battle of Asculum can cause the winning side to reconsider its long-term goals. Battles in civil wars have often decided the fate of monarchs or political factions. Famous examples include the War of the Roses, as well as the Jacobite Uprisings. Battles also affect the commitment of one side or the other to the continuance of a war, for example the Battle of Incheon and the Battle of Hue during the Tet Offensive.
A considerable amount of new knowledge about plant function comes from studies of the molecular genetics of model plants such as the Thale cress, Arabidopsis thaliana, a weedy species in the mustard family (Brassicaceae). The genome or hereditary information contained in the genes of this species is encoded by about 135 million base pairs of DNA, forming one of the smallest genomes among flowering plants. Arabidopsis was the first plant to have its genome sequenced, in 2000. The sequencing of some other relatively small genomes, of rice (Oryza sativa) and Brachypodium distachyon, has made them important model species for understanding the genetics, cellular and molecular biology of cereals, grasses and monocots generally.
Model plants such as Arabidopsis thaliana are used for studying the molecular biology of plant cells and the chloroplast. Ideally, these organisms have small genomes that are well known or completely sequenced, small stature and short generation times. Corn has been used to study mechanisms of photosynthesis and phloem loading of sugar in C4 plants. The single celled green alga Chlamydomonas reinhardtii, while not an embryophyte itself, contains a green-pigmented chloroplast related to that of land plants, making it useful for study. A red alga Cyanidioschyzon merolae has also been used to study some basic chloroplast functions. Spinach, peas, soybeans and a moss Physcomitrella patens are commonly used to study plant cell biology.
Agrobacterium tumefaciens, a soil rhizosphere bacterium, can attach to plant cells and infect them with a callus-inducing Ti plasmid by horizontal gene transfer, causing a callus infection called crown gall disease. Schell and Van Montagu (1977) hypothesised that the Ti plasmid could be a natural vector for introducing the Nif gene responsible for nitrogen fixation in the root nodules of legumes and other plant species. Today, genetic modification of the Ti plasmid is one of the main techniques for introduction of transgenes to plants and the creation of genetically modified crops.